Reenforcing bar for concrete



REENFORCING BAR OOOOOOOOO E.

CT. I?, l-QZl- 1, 4:0 4, 1 98. Patelted Jan. 24, 1922.

, UNITED ,STATES PATENT OFFICE.

i MAX J. season, or BIRMINGHAM, ALABAMA.

lj ;BEENroRoING BAR ron coNoRn'rE.

Lae-4,198.

To all whom' 'it may concern:

Be it known that I, MAx'J. GnRsoN, :a citizen of the United States ofAmerica, residing at Birmingham, in the. county of Jefferson andStateo'f vAlabama, have invented certain new and useful Improvements inIeenforcing Bars for Concrete, of which the following is aspecification.

My invention relates to a reenforcing bar for concrete which isespecially designed to be easily rolled, to present bonding surfaces tothe concrete designed to give a bond of the maximum strength, to bereadily stacked, and which is capable of being readily bent toaccommodate itself to different specifications while at the same timepossessing, in its preferred form, longitudinal stifening ribs whicheffectively strengthen the bar.

My invention more particularly contemplates the rolling of a bar havingan approximately. square cross section but with V'all corners roundedand its dominant charasteristic is the provision along each face,between the convexly curved corners, of a longitudinal groove concave incross section which is interrupted at spaced intervals with transverseribs tapering towards their straight upper edges and lying in theconcave of the groove. In my preferred arrangement the convexly curvedcorners are rolled with a tapered longitudinal center rib, the tip ofwhich lies approximately at the intersection of the projected surfaceplanes of the side faces of the bar adjacent to the rib.

.My invention will be more clearly understood by reference to theaccompanying drawings which illustrate only its preferred embodiment,and in which Fig: l is a perspective end view of a bar rolled inaccordance with its preferred design.

rig. 2 is a transverse cross section of the bar with the dotted linesshowing the projected planes of the side faces forming a square withinthe boundaries of which all portions of the bar lie.

Fig. 3 is a perspective view of a modified embodiment of my invention;and

Fig. 4 is a cross sectional viewof Fig. 3 corresponding to Fig. 2.

Similar reference numerals refer to similar parts throughout thedrawings..

In the embodiment of my .invention illustrated in i* ig. 1, I show aconcrete bar rolled with each of its four similar side faces pro- Specificaton of Letters Patent. Patented Jan. 24, 1922. I Application fileOctober 17, 1921. Serial No. 508,352.

vided with a longitudinal central concave groove' 1, the side edges ofwhich merge with a reverse curve into the convexly curved surfaces 2forming a part of each adjacent corner. Thiscurved surface 2 termi'atesat the base of a longitudinal rib 3 into which it merges with a reversecurve. This rib 3, as showncle'arly in Fig. 2, tapers slightly and lieswithin the space bounded by the intersecting planes A--A and B-B of theadj acent side faces. As thus far described all four faces of the barare similar. In each groove l I arrange at slightly spaced intervalstransverse bonding ribs which taper from their base to their top edges,which edges lie in the plane A-A or B-B and do not project above thesame. The ribs thus lie in the concave grooves and do not project abovethe plane of their respective side faces. The ribs are staggered on theseveral faces, the ribs in each opposite pair of faces lying in the sametransverse plane, which is midway between the planes in which the ribsof the other pair of faces lie.

In Fig. 3 the bar is formed with the same longitudinal groove l andtransverse ribs 4, but the corner ribs 3 are omitted and in lieu thereofthe corners are formed by the convexly curved surfaces 5 into which theconcave curve of the interposed groove 1 nerges with a reverse curve. Aswill be seen in Fig. 4, all portions of the deformed bar lie within theprojected planes of its sides which outline a square and there is anabsence throughout the bar of any sharp' corners or cutting edges whichwould militate against best results from the bar in service. By reasonof the confining of all deformations within the square defined by thefour side planes and the arrangement of the side faces soV that theirexposed edges all lie in such planes, the'bar can be stacked as easilyas a square bar while at the same time it presents a maximum bondingcharacteristic and a minimum disturbance of the main cross section ofthe bar which might affect the strength of its fiber. The corner ribs 3serve to stifien the bar and increase its bonding strength and thereforethis form is preferred. IVhile these ribs 3 stiffen the bar theynevertheless do not prevent it being easily bent as specifications mayrequire.

I have typically embodied my invention in a four sided bar with faces ofequal width, but the bar may have varied polygonal cross sections, andmay be modified in minor details Within the scope of the appendedclaims. K

Having thus described my invention what I claim as new and desire tosecurebyV Letters Patent, is

l. A concrete reenforcing bar having a plurality of longituolinal sidefacesv along the center of each of Which is rolled a concave grooveinterrupted at intervals by transverse ribs, the upper-edges of Whichlie in' a plane Contacting with the sides of their respective faces, thecorners being formed by convexly curved surfaces Which merge With aVreverse curve into the concave grooves of the two adjacent faces, and along'itudinal tapering rib lyino` along the cen-i corner surface ter ofeach convexly curve MAX J. GERSON.

Witness: I

` NOMIE WnLsH;V

